A password, a signature, a stamp seal, and the like have conventionally been used to perform personal authentication. However, personal authentication using them suffers from problems. More specifically, forgetting a password or losing a stamp may prevent the user from authenticating himself/herself. Leakage of the password or theft of the stamp may lead to the authentication of others. For this reason, a biometric authentication (biometrics authentication) technique for performing personal authentication using information such as a physical trait or behavioral trait of a user has recently been adopted. Biometric authentication is capable of preventing a third party other than the user from being authenticated. Biometric authentication cannot be forgotten or lost.
At present, fingerprint authentication using a user's fingerprint is widely prevalent as one of the readily available, reliable biometric authentication techniques. A general fingerprint authentication apparatus used for fingerprint authentication is provided with a sensor for reading a fingerprint (e.g., an optical sensor, a capacitive sensor, a field intensity measuring sensor, or a pressure-sensitive sensor). The fingerprint authentication apparatus confirms the identity of a user by forming an image of information read by means of the sensor and performing comparisons.
It is known that if a finger used at the time of fingerprint authentication has adequate moisture, a success rate of fingerprint identification improves to allow quick and accurate fingerprint authentication. A skin cream has been provided exclusively for fingerprint authentication. The skin cream provides adequate moisture to a finger and improves a success rate of fingerprint identification when the skin cream is applied to the finger in small amounts.
A solid optical fingerprint sensor capable of confirming the identity of a user by the interdigital scattered light method, even if the user uses his/her wet finger, has been introduced.
A conventional fingerprint authentication apparatus as described above is generally configured to perform authentication by reading a fingerprint of a finger mounted on a mounting section made of tempered glass or the like by means of a sensor. For example, if the fingerprint authentication apparatus is installed in an ATM at a financial institution or at the entrance of an apartment house, fingers of an indefinite number of users touch the mounting section. The fingerprint authentication apparatus may serve as a medium for the transmission of viruses or bacteria among users. The possibility of infection is expected to increase further when adequate moisture is provided to a finger for improving a success rate of fingerprint identification.
There is a need for a fingerprint authentication apparatus and a fingerprint authentication method capable of preventing infection from viruses or bacteria and quickly and accurately performing fingerprint authentication.